Buses are in widespread use in order to connect different components of a system to one another, with the result that the components can interchange data. The components connected to the bus are referred to as bus subscribers below. In this case, driver apparatuses are used to drive the bus to different states, in particular different current and/or voltage levels, in order to transmit data. In the case of CSMA/CR buses (carrier sense multiple access/collision resolution), collisions may occur if a plurality of components connected to the bus simultaneously drive the bus in order to transmit data. An example of such a CSMA/CR bus is the CAN bus (controller area network) which is in widespread use in automobile applications, for example. Another example is the RS232 bus.
In the conventional CAN bus, a driver apparatus actively drives a so-called dominant state, which represents a bit value of 0, in such a manner that a voltage difference is produced between two lines of the CAN bus. In a so-called recessive state, which represents a bit value of 1, a voltage difference between the lines of the bus conventionally changes to virtually 0 V without active driving via a resistor which connects the lines. If, during this conventional approach, a driver apparatus of one bus subscriber drives the bus to a dominant state, while the driver apparatus of another bus subscriber is passively switched to a recessive state, the dominant state dominates and the bus overall assumes the dominant state with a voltage difference between the bus lines.
In this conventional approach, so-called ringing, that is to say oscillations on the bus which can interfere with communication, can occur during the transition from the dominant state to the recessive state. In order to suppress this ringing, approaches to also actively drive the recessive state or at least actively drive a transition from the dominant state to the recessive state are pursued. However, this may be problematic with respect to collisions if one bus subscriber actively drives the bus to the dominant state and another bus subscriber simultaneously actively drives the bus to the recessive state.